*{
  padding: 0;
  margin: 0;
}
body{
  width: 100vw;
  height: 100vh;
  overflow: hidden;
  background: url('../images/9.jpg') no-repeat;
  background-size: cover;
  background-position: center center;
}
.container{
  width: 100%;
  height: 100%;
  display: flex;
}
.iconfont{
  color: #fff;
  font-size: 24px;
}
/* 左边导航栏 */
.left-box{
  width: 250px;
  height: 100%;
  background-color: rgba(0,0,0,0.65);
  /* 背景模糊 */
  backdrop-filter: blur(30px);
  position: relative;
  display: flex;
  flex-direction: column;
  font-size: 14px;
  color: #fff;
  transition: 0.5s ease;
  white-space: nowrap;
}
.left-box ul{
  list-style: none;
  width: 90%;
  margin: 25px auto;
  /* 高度铺满 */
  flex: 1;
}
.left-box li{
  height: 46px;
  display: flex;
  align-items: center;
  padding-left: 12px;
  border-radius: 10px;
  cursor: pointer;
  transition: 0.3s;
}
.left-box li.active,
.left-box li.active:hover{
  background-color: rgba(255, 255, 255, 0.2);
}
.left-box li:hover{
  background-color: rgba(255, 255, 255, 0.1);
}
/* 设置分割线样式 */
.left-box hr{
  width: 90%;
  margin: 18px auto;
  border: none;
  border-top: 1px solid rgba(255, 255, 255, 0.2);
}
.left-box .iconfont{
  margin-right: 16px;
}
/* 用户区 */
.user-info{
  border-top: 1px solid rgba(255, 255, 255, 0.2);
  display: flex;
  align-items: center;
  padding: 20px;
}
.user-info img{
  width: 40px;
  height: 40px;
  border-radius: 50%;
  /* object-fit CSS 属性指定可替换元素（例如：<img> 或 <video>）的内容应该如何适应到其使用高度和宽度确定的框。 */
  object-fit: cover;
  margin-right: 14px;
}
.user-info span{
  flex: 1;
}
.user-info .iconfont{
  font-size: 16px;
  margin-right: 0;
}
/* 右侧区域 */
.right-box{
  backdrop-filter: blur(50px);
  flex: 1;
  position: relative;
  display: flex;
  flex-direction: column;
}
.right-box .top{
  margin: 25px 35px;
  display: flex;
  align-items: center;
  height: 46px;
}
.top .current-tag{
  flex: 1;
  color: #fff;
  font-weight: 600;
}
.top .btn{
  width: 32px;
  height: 32px;
  display: flex;
  /*图标居中 */
  justify-content: center;
  align-items: center;
  border-radius: 50%;
}
.top .btn:last-child{
  background-color: #446dff;
  margin-left: 20px;
}
/* 中间部分 */
.right-box .middle{
  flex: 1;
  display: flex;
  justify-content: center;
  align-items: center;
  color: rgb(249, 244, 244);
  font-size: 6vw;
  font-weight: bold;
  text-transform: uppercase;
}
.right-box  .handler{
  width: 10px;
  height: 50px;
  position: absolute;
  left: 10px;
  top: 50%;
  transform: translateY(-50%);
  z-index: 1;
  cursor: pointer;
  opacity: 0;
  transition: opacity 0.3s;
}
.right-box  .handler::after,
.right-box  .handler::before{
  content: "";
  background-color: rgba(255, 255, 255, 0.2);
  position: absolute;
  left: 5px;
  width: 100%;
  height: 50%;
  border-radius: 10px 10px 0 0;
  transition: 0.1s
}
.right-box  .handler::after{
  bottom: 0;
  border-radius: 0 0 10px 10px;
}
.right-box:hover .handler{
  opacity: 1;
}
/* hover时的before */
.right-box .handler:hover::before{
  /* 偏离水平轴x的角度 ，越大就会越长 90度为0 */
  transform: skewX(-20deg);
}
.right-box .handler:hover::after{
  transform: skewX(20deg);
}
.right-box .handler.close:hover::before{
  transform: skewX(20deg);
}
.right-box .handler.close:hover::after{
  transform: skewX(-20deg);
}